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In the recent era of green and sustainable energy, the demand for effective and efficient energy harvesting has dramatically increased. Piezoelectric energy harvesting, which converts mechanical energy into electrical energy, is considered a viable strategy to achieve this goal. Janus-type nanomaterial, a noncentrosymmetric material with different elemental species in the upper and lower atomic layers, has gained interest due to its exotic properties compared to conventional bulk and symmetric materials. In this work, we systematically design and investigate a new class of Janus nanomaterials with enhanced intrinsic polarization via the successive ionic exchange method. Multiple layers of stability standards, including both thermodynamic and dynamic stabilities, are employed in the high-throughput screening procedure of novel Janus-type nanomaterials. The newly proposed Janus-type nanomaterials exhibit more than 10 times higher piezoelectric response compared to that of reported low-dimensional materials and even comparable to that of bulk materials.
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BACKGROUND: There are limited conventional chemotherapy options for biliary tract cancers (BTCs), a heterogenous group of lethal, rare malignancies. The receptor tyrosine kinase (RTK) is closely associated with the progression of human malignancies through the regulation of cell cycle. Overexpression or amplification of RTKs has been investigated as a potential biomarker and therapeutic target in BTC; herein, we investigate the value of such interventions. MATERIALS AND METHODS: Overexpression of RTK proteins was examined by immunohistochemistry in 193 BTC samples, of which 137 were gallbladder carcinoma, 29 were perihilar cholangiocarcinoma, and 27 were intrahepatic cholangiocarcinoma. Silver in situ hybridization of MET and HER2 was performed to assess gene amplification. RESULTS: In the entire cancer group, gallbladder, perihilar, and intrahepatic, MET amplification rates were 15.7%, 19.0%, 3.4%, and 14.8%, respectively, and of HER2 amplification rates were 22.4%, 27.2%, 17.2%, and 3.7%, respectively. MET and HER2 protein expressions were significantly correlated with their gene amplification status. RTKs were significantly associated with adverse clinicopathologic features such as advanced pT category and lymph node metastasis. Overall survival was significantly shorter in MET-amplified (Pâ =â .024) and EGFR-overexpressed cases (Pâ =â .045). Recurrence-free survival was significantly correlated with HER2-amplified (Pâ =â .038) and EGFR-overexpressed cases (Pâ =â .046) in all patient groups. Overall and recurrence-free survival were significantly shorter in patients who were double positive for HER2 and EGFR. CONCLUSION: Our data suggested that MET, HER2, and EGFR might be potential therapeutic targets and that their co-expression is a strong prognostic factor for BTCs.
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Neoplasias del Sistema Biliar , Receptores ErbB , Amplificación de Genes , Proteínas Proto-Oncogénicas c-met , Receptor ErbB-2 , Humanos , Femenino , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Proteínas Proto-Oncogénicas c-met/genética , Proteínas Proto-Oncogénicas c-met/metabolismo , Masculino , Persona de Mediana Edad , Pronóstico , Neoplasias del Sistema Biliar/genética , Neoplasias del Sistema Biliar/patología , Neoplasias del Sistema Biliar/metabolismo , Neoplasias del Sistema Biliar/tratamiento farmacológico , Receptores ErbB/genética , Receptores ErbB/metabolismo , Anciano , Adulto , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Anciano de 80 o más AñosRESUMEN
Introduction of interstitial dopants has opened a new pathway to optimize nanoparticle catalytic activity for, e.g., hydrogen evolution/oxidation and other reactions. Here, we discuss the stability of a property-enhancing dopant, B, introduced through the controlled synthesis of an electrocatalyst Pd aerogel. We observe significant removal of B after the hydrogen oxidation reaction. Ab initio calculations show that the high stability of subsurface B in Pd is substantially reduced when H is adsorbed/absorbed on the surface, favoring its departure from the host nanostructure. The destabilization of subsurface B is more pronounced, as more H occupies surface sites and empty interstitial sites. We hence demonstrate that the H2 fuel itself favors the microstructural degradation of the electrocatalyst and an associated drop in activity.
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Metaplastic carcinoma of the breast is a heterogeneous group of neoplasms with mixed epithelial and mesenchymal differentiation. Metaplastic carcinoma of the breast is a rare and aggressive malignancy, with high recurrence and metastasis. Metaplastic carcinoma with chondroid differentiation is an uncommon subtype that tends to have a relatively good prognosis than that of other subtypes. We report the imaging features of three cases of pathologically proven metaplastic carcinoma with chondroid differentiation as follows: a high-density mass with amorphous or coarse heterogeneous calcifications on mammography; a microlobulated or partially indistinct, complex cystic, and solid mass on sonography; and a relatively circumscribed or partially indistinct, irregular mass with heterogeneous T2 high-signal intensity and heterogeneous or rim enhancement with initial fast enhance ment and delayed washout on MRI.
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Infection with high-risk (HR) Human Papillomavirus (HPV) is associated with the development of precancerous lesions or invasive carcinoma of the uterine cervix. Thus, the high viral load (VL) of HR-HPV DNA currently serves as a representative quantitative marker for cervical cancer. However, the clinical significance of low HPV DNA VL remains undetermined. This study aimed to evaluate the clinical association between the low HPV DNA VL and cytology/histologic diagnosis of cervical samples. We searched the electronic medical databases for the resultant analyses of HPV genotyping among patients who underwent treatment for any cervical lesion or who had undergone gynecological examinations with any positive HPV results according to the national cancer screening service between 2015 and 2016. HPV testing with genotyping and semi-quantitative VL measurement was conducted using an AnyplexTM II H28 Detection assay (H28 assay, Seegene, Seoul, Republic of Korea). The H28 assay is a multiplex semi-quantitative real-time PCR test using the tagging of oligonucleotide cleavage and extension (TOCE) technology. The VL was semi-quantified as high (3+; positive signal before 31 PCR cycles), intermediate (2+; positive between 31 and 39 PCR cycles), or low (1+; positive after 40 PCR cycles). Out of 5940 HPV VL analyses, 356 assays (5.99%) were reported as low VL (1+) of HPV DNA. Matched cytology diagnoses were mostly negative findings (n = 347, 97.5%), except for seven cases of atypical squamous cells of undetermined significance (1.9%) and two cases of atypical glandular cells (0.6%). During the follow-up periods, abnormal cytologic diagnoses were identified, including one case of high-grade squamous intraepithelial lesion (HSIL) and two low-grade squamous intraepithelial lesions (LSILs). The matched, confirmative histologic diagnosis of HSIL cytology was compatible with chronic inflammation, wherein the two LSILs had regular check-ups. None revealed clinically concerned outcomes associated with HPV-related squamous lesions. The cytology was most likely negative for malignancy when the VL of HPV DNA was low (1+). Additional strategic monitoring and management may thus be unnecessary.
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Fuel cells recombine water from H2 and O2 thereby can power, for example, cars or houses with no direct carbon emission. In anion-exchange membrane fuel cells (AEMFCs), to reach high power densities, operating at high pH is an alternative to using large volumes of noble metals catalysts at the cathode, where the oxygen-reduction reaction occurs. However, the sluggish kinetics of the hydrogen-oxidation reaction (HOR) hinders upscaling despite promising catalysts. Here, the authors observe an unexpected ingress of B into Pd nanocatalysts synthesized by wet-chemistry, gaining control over this B-doping, and report on its influence on the HOR activity in alkaline conditions. They rationalize their findings using ab initio calculations of both H- and OH-adsorption on B-doped Pd. Using this "impurity engineering" approach, they thus design Pt-free catalysts as required in electrochemical energy conversion devices, for example, next generations of AEMFCs, that satisfy the economic and environmental constraints, that is, reasonable operating costs and long-term stability, to enable the "hydrogen economy."
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Mucinous adenocarcinoma of the endometrium is heterogeneous, consisting of endometrioid adenocarcinoma composed of >50% mucinous cells, low-grade mucinous adenocarcinoma, microglandular adenocarcinoma, and gastric (gastrointestinal)-type adenocarcinoma. Previous studies have reported that papillary mucinous metaplasia is a possible precancerous lesion of mucinous adenocarcinoma with frequent KRAS mutations. Recently, we encountered a case of pure mucinous adenocarcinoma of the endometrium with concurrent papillary mucinous metaplasia in a 35-year-old woman. She underwent 6-month hormonal therapy for atypical endometrial hyperplasia. A follow-up biopsy led to a diagnosis of mucinous adenocarcinoma; therefore, total hysterectomy was performed. The tumor showed abundant intracytoplasmic mucin and mild-to-moderate cytologic atypia with papillary architecture. KRAS mutation analysis revealed a point mutation from GGT to GTT in codon 12. Although papillary mucinous metaplasia showed an overexpression of p16INK4, especially in the intragrandular papillary tufts, and a low MKi67 labeling index, overt mucinous adenocarcinoma with a loss of P16INK4a expression showed a high proliferating index of MKI67. The mass presented with stage ÐA disease. During follow-up, the patient was stable and showed no recurrence. Considering the histologic similarity and incidence of KRAS mutations between papillary mucinous metaplasia and mucinous adenocarcinoma, papillary mucinous metaplasia may be a precancerous lesion for a subset of mucinous adenocarcinoma of the endometrium.
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Metal nanogels combine a large surface area, a high structural stability, and a high catalytic activity toward a variety of chemical reactions. Their performance is underpinned by the atomic-level distribution of their constituents, yet analyzing their subnanoscale structure and composition to guide property optimization remains extremely challenging. Here, we synthesized Pd nanogels using a conventional wet chemistry route, and a near-atomic-scale analysis reveals that impurities from the reactants (Na and K) are integrated into the grain boundaries of the poly crystalline gel, typically loci of high catalytic activity. We demonstrate that the level of impurities is controlled by the reaction condition. Based on ab initio calculations, we provide a detailed mechanism to explain how surface-bound impurities become trapped at grain boundaries that form as the particles coalesce during synthesis, possibly facilitating their decohesion. If controlled, impurity integration into grain boundaries may offer opportunities for designing new nanogels.
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Transitional cell metaplasia (TCM) of the uterine cervix and vagina is typically seen in patients with adrenogenital syndrome with high serum androgen levels and in those under androgen treatment as well as in some peri/postmenopausal women. Considering that TCM occurs in patients with increased serum androgen levels, a microenvironment with altered sex hormones might be involved in the urothelial-like differentiation observed in TCM. To investigate a histogenetic role of androgen in TCM development, we compared the distribution patterns and intensity of androgen receptor (AR), estrogen receptor (ER), GATA3 (a transcription factor involved in androgen regulation), Ki-67, and AKR1C3 (an enzyme involved in androgen biosynthesis) expression in normal exocervical mucosa in young women (n = 25), senile atrophy (n = 23), and TCM (n = 29). In TCM, AR, ER, AKR1C3, and GATA3, expression was stronger and significantly increased upward into the intermediate and superficial layers compared with the senile atrophic mucosa and normal mucosa in young women. The epithelial layer in TCM is thicker than that in senile atrophic mucosa, although both conditions may occur in the same age group. Proliferation in TCM was significantly lower than that in young women but slightly higher than that in senile atrophy. Considering the conversion activity of AKR1C3, thicker epithelial layers in TCM compared with those in senile atrophy might be due to increased conversion of androstenedione to testosterone via increased AKR1C3 activity, increased conversion of testosterone to 17ß-estradiol by aromatization, and AR activation.
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Cuello del Útero/patología , Posmenopausia/metabolismo , Anciano , Miembro C3 de la Familia 1 de las Aldo-Ceto Reductasas/metabolismo , Diferenciación Celular , Cuello del Útero/metabolismo , Femenino , Factor de Transcripción GATA3/metabolismo , Humanos , Inmunohistoquímica , Metaplasia/metabolismo , Metaplasia/patología , Persona de Mediana Edad , Receptores Androgénicos/metabolismo , Receptores de Estrógenos/metabolismoRESUMEN
Nanocrystals of group 5 tetradymites M2X3 (where M = Bi and Sb, X = Se and Te) are of high technological relevance in modern topological nanoelectronics. However, there is a current lack of a systematic understanding to predict the preferred nanocrystal morphology in experiments where commonly-used equilibrium thermodynamic models appear to fail. In this work, using first-principles DFT calculations with a rationally-extended ab initio atomistic thermodynamics approach coupled to implicit solvation models and Gibbs-Wulff shape constructions, we demonstrate that this absence of predictive power stems from the limitation of equilibrium thermodynamics. By re-tracing and carefully addressing with a more realistic chemical potential definition, we illustrate this shortcoming can be overcome and afford a more rational route to size-engineer and shape-design highly-functional group 5 tetradymite nanoparticles for targeted applications.
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BACKGROUND: Dickkopf-1 (DKK1) is a Wnt/ß-catenin pathway antagonist related to gastric cancer (GC) carcinogenesis. However, the prognostic role of combined DKK1 and ß-catenin expression in advanced GC (AGC) is not clear. METHODS: In total, 158 patients with AGC who underwent gastric resection were enrolled in this study. DKK1 and ß-catenin expression was evaluated in whole tumor sections by immunohistochemistry. RESULTS: DKK1 expression was high in 73 (46.2%) patients, while ß-catenin expression was positive in 51 (32.3%) patients. The expression of DKK1 was positively correlated with that of ß-catenin (P < 0.001). The combined expression of DKK1 and ß-catenin was significantly associated with high N stage (N2 and N3) (P = 0.042). In addition, patients with high DKK expression demonstrated poorer overall (OS) (P < 0.001) and disease-free survival (DFS) (P = 0.001). However, there were no differences between high DKK1 expression with ß-catenin positivity and high DKK1 expression with ß-catenin negativity (OS, P = 0.379: DFS, P = 0.255). Multivariate analysis revealed that high DKK1 alone or high DKK1 with ß-catenin positivity were independent prognostic factors for both OS (high DKK1: hazard ratio [HR], 2.130; 95% confidence interval [CI]; 1.370-3.312, P = 0.001; high DKK1 with ß-catenin positivity: HR, 2.140; 95% CI, 1.343-3.409: P = 0.001) and DFS (high DKK1: HR, 2.092; 95% CI, 1.180-3.708; P = 0.012; high DKK1 with ß-catenin positivity: HR, 2.357; 95% CI, 1.291-4.306; P = 0.005). CONCLUSION: Our results indicate that high DKK1 expression regardless of ß-catenin positivity is a crucial prognostic factor for predicting tumor recurrence and survival in patients with resected AGC.
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Biomarcadores de Tumor/análisis , Péptidos y Proteínas de Señalización Intercelular/biosíntesis , Neoplasias Gástricas/patología , beta Catenina/biosíntesis , Adulto , Anciano , Anciano de 80 o más Años , Supervivencia sin Enfermedad , Femenino , Humanos , Péptidos y Proteínas de Señalización Intercelular/análisis , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Pronóstico , Modelos de Riesgos Proporcionales , Neoplasias Gástricas/mortalidad , beta Catenina/análisisRESUMEN
CONTEXT: - Papillary immature metaplasia (PIM) is a known papillary cervical lesion associated with low-risk human papillomavirus (LR-HPV). OBJECTIVE: - To evaluate additional clinicopathologic features and the HPV genotypes of PIM and discuss the presumptive cell of origin. DESIGN: - A total of 26 PIM cases were evaluated by p16INK4a, cytokeratin (CK) 7, and CK17 immunohistochemical stainings. Human papillomavirus genotyping was performed, by using HPV DNA Chip, HPV polymerase chain reaction (PCR), and real-time PCR. RESULTS: - Histologically, PIM forms either a papillary mass (n = 21 of 26, 81%) or a slightly elevated/flat plaque (n = 5, 19%). All cases contain variable amounts of mucinous epithelia within the lesions. Koilocytosis was identified in 15 of the 26 cases (58%). Sixteen cases (61%) were associated with LR-HPV (types 6, 11, or 42), but 3 cases (12%) with high-risk (HR) HPV (16, 16/18, and 33), 2 cases (8%) with mixed LR- and HR-HPV (6/16 and 11/58), while 2 cases (8%) were negative, but p16INK4a immunostaining showed nonblock positivity in all cases. Eight (31%) had high-grade squamous intraepithelial lesion (HSIL) in the adjacent mucosa, 4 (50%) of which showed direct continuity. Identical HPV subtypes were confirmed in separately microdissected cases from PIM and adjacent HSIL. Most lesions (n = 24, 92%) expressed CK17 (reserve cell marker) in a bottom-heavy pattern and CK7 (squamocolumnar junction [SCJ] marker) in a top-heavy pattern, while most cases of low-grade squamous intraepithelial lesion (LSIL) were negative for both markers. CONCLUSIONS: - Our results suggest that PIM is a distinct subset of LSIL showing a productive HPV infection, but PIM involves the transformation zone and is proximal to SCJ, while LSIL is mostly from ectocervix or distal to the SCJ.
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Cuello del Útero/patología , Lesiones Intraepiteliales Escamosas de Cuello Uterino/patología , Adulto , Biomarcadores de Tumor/metabolismo , Cuello del Útero/metabolismo , Cuello del Útero/virología , Femenino , Técnicas de Genotipaje , Humanos , Inmunohistoquímica , Metaplasia , Persona de Mediana Edad , Clasificación del Tumor , Papillomaviridae/genética , Infecciones por Papillomavirus/complicaciones , Infecciones por Papillomavirus/diagnóstico , Infecciones por Papillomavirus/virología , Fenotipo , Lesiones Intraepiteliales Escamosas de Cuello Uterino/diagnóstico , Lesiones Intraepiteliales Escamosas de Cuello Uterino/metabolismo , Lesiones Intraepiteliales Escamosas de Cuello Uterino/virologíaRESUMEN
The impact of an electrochemical environment on the thermodynamic stability of polar oxide surfaces is investigated for the example of ZnO(0001) surfaces immersed in water using density functional theory calculations. We show that solvation effects are highly selective: They have little effect on surfaces showing a metallic character, but largely stabilize semiconducting structures, particularly those that have a high electrostatic penalty in vacuum. The high selectivity is shown to have direct consequences for the surface phase diagram and explains, e.g., why certain surface structures could be observed only in an electrochemical environment.
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Many recent studies have demonstrated that several known and unknown viruses infect many horticultural plants. However, the elucidation of a viral population and the understanding of the genetic complexity of viral genomes in a single plant are rarely reported. Here, we conducted metatranscriptome analyses using six different peach trees representing six individual peach cultivars. We identified six viruses including five viruses in the family Betaflexiviridae and a novel virus belonging to the family Tymoviridae as well as two viroids. The number of identified viruses and viroids in each transcriptome ranged from one to six. We obtained 18 complete or nearly complete genomes for six viruses and two viroids using transcriptome data. Furthermore, we analyzed single nucleotide variations for individual viral genomes. In addition, we analyzed the amount of viral RNA and copy number for identified viruses and viroids. Some viruses or viroids were commonly present in different cultivars; however, the list of infected viruses and viroids in each cultivar was different. Taken together, our study reveals the viral population in a single peach tree and a comprehensive overview for the diversities of viral communities in different peach cultivars.
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Frutas/genética , Frutas/virología , Prunus persica/genética , Prunus persica/virología , Genoma Viral/genética , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/virología , ARN Viral/genética , Transcriptoma/genética , Viroides/genéticaRESUMEN
BACKGROUND/AIMS: Endoscopic resection is the first-line treatment for rectal neuroendocrine tumors (NETs) measuring <1 cm and those between 1 and 2 cm in size. However, conventional endoscopic resection cannot achieve complete resection in all cases. We aimed to analyze clinical outcomes of precut endoscopic mucosal resection (EMR-P) used for the management of rectal NET. METHODS: EMR-P was used to treat rectal NET in 72 patients at a single tertiary center between 2011 and 2015. Both, circumferential precutting and EMR were performed with the same snare device in all patients. Demographics, procedural details, and histopathological features were reviewed for all cases. RESULTS: Mean size of the tumor measured endoscopically was 6.8±2.8 mm. En bloc and complete resection was achieved in 71 (98.6%) and 67 patients (93.1%), respectively. The mean time required for resection was 9.0±5.6 min. Immediate and delayed bleeding developed in six (8.3%) and 4 patients (5.6%), respectively. Immediate bleeding observed during EMR-P was associated with the risk of delayed bleeding. CONCLUSIONS: Both, the en bloc and complete resection rates of EMR-P in the treatment of rectal NETs using the same snare for precutting and EMR were noted to be high. The procedure was short and safe. EMR-P may be a good treatment choice for the management of rectal NETs.
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OBJECTIVE: Caveolin-1 (Cav-1), as the main component of caveolae, has complex roles in tumourigenesis in human malignancies. We investigated Cav-1 in primary and metastatic tumor cells of gastric cancer (GC) and its association with clinical outcomes. METHODS: We retrieved 145 cases of GC who had undergone curative gastrectomy. The expression levels of Cav-1 was evaluated by immunohistochemistry, and its association with clinicopathological parameters and patient survival was analyzed. RESULTS: High expression of Cav-1 protein of the GC in the stomach and metastatic lymph node was 12.4% (18/145) and 16.5% (15/91). In the multivariate analysis, tumoral Cav-1 protein in metastatic lymph node showed prognostic significance for relapse-free survival (RFS, HR, 3.934; 95% CI, 1.882-8.224; P = 0.001) and cancer-specific survival outcome (CSS, HR, 2.681; 95% CI, 1.613-8.623; P = 0.002). Among the GCs with metastatic lymph node, it remained as a strong indicator of poor prognosis for RFS (HR, 3.136; 95% CI, 1.444-6.810; P = 0.004) and CSS (HR, 2.509; 95% CI, 1.078-5.837; P = 0.032). CONCLUSION: High expression of tumoral Cav-1 protein in metastatic lymph node is associated with unfavorable prognosis of curative resected GC, indicating the potential of novel prognostic markers.
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The non-receptor tyrosine phosphatase SHP2 has scaffolding functions in signal transduction cascades downstream of growth receptors. A recent study suggested that SHP2 acts as a tumor suppressor during hepatocellular carcinoma (HCC) development. Herein we examined whether SHP2 links the HBx-NF-κB pathway to EGFR signaling during HCC development. The overexpression of HBx or NF-κB led to increased SHP2 expression via NF-κB binding to the Shp2 promoter. EGF treatment induced ERK activation as well as the rapid assembly of SHP2, EGFR, and Gab1. Upon LPS stimulation, NF-κB-SHP2-ERK activation and phosphorylated STAT3 levels exhibited a negative correlation in vitro. By contrast, in patients with HBV-associated HCC, NF-κB-SHP2-ERK and IL-6-JAK-STAT3 pathway activity levels were concomitantly higher in adjacent non-neoplastic tissues than in HCC tissues. The immunohistochemical analysis of 162 tissues of patients with HCC revealed that SHP2 levels were significantly higher in non-neoplastic background tissues than in corresponding HCC tissues and considerably increased in background liver tissues with advanced fibrosis (P < 0.001). SHP2 expression increased gradually from normal liver to chronic hepatitis, cirrhosis, and background liver with a dysplastic nodule, but was decreased or lost in dysplastic nodules and HCC. This is the first report to describe the existence of the HBx-NF-κB-SHP2 pathway, linking HBV infection to the EGFR-RAS-RAF-MAPK pathway in the liver. SHP2 depletion from the negative crosstalk between NF-κB and STAT3 accelerates HCC development.
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Carcinoma Hepatocelular/etiología , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/etiología , Neoplasias Hepáticas/metabolismo , FN-kappa B/metabolismo , Proteína Tirosina Fosfatasa no Receptora Tipo 11/genética , Transactivadores/metabolismo , Adulto , Anciano , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/cirugía , Línea Celular Tumoral , Femenino , Fibrosis , Regulación Neoplásica de la Expresión Génica , Virus de la Hepatitis B/fisiología , Humanos , Cirrosis Hepática/etiología , Cirrosis Hepática/metabolismo , Cirrosis Hepática/patología , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/cirugía , Masculino , Persona de Mediana Edad , Modelos Biológicos , Clasificación del Tumor , Estadificación de Neoplasias , Regiones Promotoras Genéticas , Unión Proteica , Proteína Tirosina Fosfatasa no Receptora Tipo 11/metabolismo , Factor de Transcripción STAT3/metabolismo , Transducción de Señal , Proteínas Reguladoras y Accesorias Virales , Proteínas ras/metabolismoRESUMEN
Phase ordering in the mixed-valence oxide Sb2O4 has been examined by density functional theory (DFT) calculations. We find that the ground-state total energies of the two phases (α and ß) are almost degenerate and are highly sensitive to the choice of the approximation to the exchange correlation (xc) functional used in our calculations. Interestingly, with the inclusion of the zero-point energy corrections, the α phase is predicted to be the ground state polymorph for most xc functionals used. We also illustrate the pronounced stereochemical activity of Sb in these polymorphs of Sb2O4, setting an exception to the Keve and Skapski rule. Here, we find that the actual bonding in the α phase is more asymmetric, while the anomalous stability of the ß phase could be rationalized from kinetic considerations. We find a non-negligible activation barrier for this α-ß phase transition, and the presence of a saddle point (ß phase) supports the separation of Sb(III) over a continuous phase transition, as observed in experiments.